fix: add language detection from app_settings and fix activity_logs schema

- Enhanced language detection priority in email processor:
  1. Event-specific language
  2. App settings general_default_language (NEW)
  3. Email config default_language
  4. Domain-based detection
- Fixed activity_logs insertion error by using logActivity function
- Fixed 500 error on resend email endpoint
- Emails now respect language selected in settings page

backend/scripts/test-german-emails.js

@@ -0,0 +1,85 @@
+const { db } = require('../src/database/db');
+const { processTemplate } = require('../src/services/emailProcessor');
+
+async function testGermanEmails() {
+  try {
+    console.log('=== Testing German Email Templates ===\n');
+    
+    // Test variables
+    const testVars = {
+      host_name: 'Max Mustermann',
+      event_name: 'Hochzeit Schmidt',
+      event_date: '15.07.2024',
+      gallery_link: 'https://example.com/gallery/test',
+      gallery_password: 'test1234',
+      expiry_date: '15.08.2024',
+      days_remaining: '7',
+      welcome_message: 'Herzlich willkommen zu unserer Hochzeitsgalerie!',
+      archive_size: '250 MB',
+      archive_date: '16.08.2024',
+      photo_count: '347',
+      admin_email: '[email protected]',
+      eventId: 1
+    };
+    
+    const templates = await db('email_templates').select('*');
+    
+    for (const template of templates) {
+      console.log(`\n========== ${template.template_key.toUpperCase()} ==========`);
+      
+      // Process German version
+      const germanResult = await processGermanTemplate(template, testVars);
+      
+      console.log('\n--- GERMAN VERSION ---');
+      console.log('Subject:', germanResult.subject);
+      console.log('\nHTML Preview (first 500 chars):');
+      console.log(germanResult.htmlBody.substring(0, 500) + '...\n');
+      
+      // Check for any remaining English text
+      const englishWords = ['Dear', 'Gallery', 'Details:', 'Link:', 'Password:', 'days', 'Thank you'];
+      const foundEnglish = englishWords.filter(word => 
+        germanResult.htmlBody.includes(word) || germanResult.subject.includes(word)
+      );
+      
+      if (foundEnglish.length > 0) {
+        console.log('⚠️  WARNING: Found English words:', foundEnglish.join(', '));
+      } else {
+        console.log('✅ No English words found in German template');
+      }
+    }
+    
+    await db.destroy();
+  } catch (error) {
+    console.error('Error:', error);
+    await db.destroy();
+    process.exit(1);
+  }
+}
+
+async function processGermanTemplate(template, variables) {
+  // Process template as German
+  const subjectField = 'subject_de';
+  const htmlField = 'body_html_de';
+  const textField = 'body_text_de';
+  
+  let subject = template[subjectField] || template.subject || '';
+  let htmlBody = template[htmlField] || template.body_html || '';
+  let textBody = template[textField] || template.body_text || '';
+  
+  // Replace variables
+  Object.keys(variables).forEach(key => {
+    const regex = new RegExp(`{{${key}}}`, 'g');
+    subject = subject.replace(regex, variables[key]);
+    htmlBody = htmlBody.replace(regex, variables[key]);
+    textBody = textBody.replace(regex, variables[key]);
+  });
+  
+  // Handle conditionals (simplified)
+  htmlBody = htmlBody.replace(/{{#if welcome_message}}[\s\S]*?{{\/if}}/g, (match) => {
+    return variables.welcome_message ? match.replace(/{{#if welcome_message}}|{{\/if}}/g, '') : '';
+  });
+  
+  return { subject, htmlBody, textBody };
+}
+
+testGermanEmails();